Farley Cleghorn, MD | Source | Chief Medical Officer at Palladium

AstraZeneca has paused their Phase III trials. I see this as a relatively routine issue and if it happened outside of the current coronavirus context, no one would blink. Given the stakes the attention is immense. While all the coronavirus candidate vaccines appear relatively reactogenic (high occurrence of mild side effects), this volunteer apparently had what we refer to as a severe adverse event (SAE) and has been hospitalized. Any SAE must be assumed to be related to the vaccine (even if the volunteer developed appendicitis, for instance) and thoroughly investigated and reported to the Data Safety and Monitoring Board. So, all is going according to plan despite this pause.

The news today on the coronavirus is mixed. The epidemic continues to break records in the United States, with approximately 250,000 preventable deaths. The interim results released by Pfizer yesterday are not conclusive, but they are encouraging. It should be noted, though, that the vaccine does not prevent transmission of the virus - it prevent the clinical outcome of the virus, which is COVID-19. This means that we cannot relax our infection control measures even after we start administering a vaccine like the Pfizer vaccine (such as social distancing, hygiene, mask-wearing). We simply don't know what the impact will be on transmission. Making and avoiding crowds and indoor spaces will still have to be practiced even as we roll this vaccine out. But it will give comfort to high-risk groups. Even if this vaccine pans out, we're well into next year before we have a reasonable distribution to the people who need it most.

We’re going through a sort of firestorm right now of [Omicron] transmission, and that rapidly burns out the susceptibles. One of the quick key questions is, if you get Omicron once and you’re unvaccinated, can you get it again? We don’t know the answer. Experts likely will have a better idea of the future trajectory of the variant—and its impact—in the U.S. after January. Deaths and hospitalizations tend to lag case numbers, and many of the current figures still reflect Delta variant infections.